The invention relates to respirators and, in particular, to apparatus and methods for releasably securing respirator devices, namely masks, hoods and the like, to users.
Monoplace (one-person) and multiplace (two or more persons) hyperbaric chambers exist for various therapeutic treatments. Currently, a one hundred percent oxygen atmosphere is maintained within the chamber for the occupants of such chambers. There are dangers inherent in such an oxygen rich environment, in the form of increased flammability of materials, lowered ignition temperatures and increased rates of fire propagation. Several fires within such monoplace hyperbaric chambers have already been reported in Japan.
Respirator masks or hoods have not been used to supply oxygen to the occupants of such chambers so that a noncombustible or less combustible atmosphere may be used to pressurize the chambers. This is due to the inherent dangers of oxygen toxicity to the chamber occupant. Oxygen toxicity is the effect on the human nervous system of oxygen breathed at above atmospheric pressures. Symptoms of oxygen toxicity include seizures similar to epilepsy and may also include vomiting. If chamber occupants were equipped with masks or hoods to provide pressurized oxygen, vomitus from the patient would be contained by the mask or hood and could lead to drowning or asphyxiation. Monoplace hyperbaric chambers are designed to receive only a single occupant. Any attendant would be located outside of the chamber. The only way an attendant can reach an occupant within a pressurized chamber is to first depressurize the chamber. The occupant within a pressurized chamber can be put to further risk if the chamber is depressurized too rapidly. Thus, the use of a respirator mask or hood in such environments is fraught with dangers to the users and, for that reason, has not been adopted despite the significant risk of injury or death to users that exists from fire in such chambers.
It is an initial object to provide a safe apparatus and method for removal of a respiratory mask or hood from the face of a person, either automatically or manually remote from the mask or hood, or both.
It is yet another object of the invention to provide an apparatus and method for the safe use of a respirator mask or hood in a sealed monoplace hyperbaric chamber.
It is yet another object of the invention to provide an apparatus and method to attach a respirator mask or hood to a user only when the minimum breathable gas pressure being supplied to the respirator mask or hood is at least as great as the minimum operating pressure required by the mask or hood for safe use.
It is yet another object of the invention to provide an apparatus whereby a respiratory mask or hood attached to a user will automatically release from the user when the pressure of breathable gas supplied to the respiratory mask or hood falls below a minimum pressure required for proper operation of the mask or hood.
It is yet another object of the invention to provide an apparatus and method to release a respirator mask or hood from an unconscious or otherwise unresponsive user in the event of exhaustion of gas supply to the respirator mask or hood or failure of one or more components of the gas supply system apparatus or the provision of incorrect gas supply pressure due to operator error.
Each of the various forms of the invention fulfills at least one of these objects.
In one aspect, the invention is an automatic release apparatus to use with a respirator device configured to cover at least part of a wearer""s face so as to provide breathable gas to at least the wearer""s mouth or nose, the automatic release apparatus comprising: a securement device configured to fit around at least part of a respirator device wearer""s head; and a coupling configured to releasably secure a respirator device with the securement device to the wearer""s head, the coupling including at least a first member and an actuator operatively yet releasably connected with the first member, the actuator having a gas inlet and being coupled with the first member so as to hold the first member in engagement to maintain the coupling at least while the actuator is pressurized by gas supplied to the actuator gas inlet and to release the first member to break the coupling and release the respirator device when the actuator is insufficiently pressurized.
In another aspect, the invention is a method of automatically releasing a respirator device at least from a wearer""s face comprising the steps of: supplying pressurized breathable gas at least at a predetermined initial minimum pressure above ambient atmospheric pressure around the respirator device simultaneously to the respirator device and to an actuator of a coupling releasably securing the respirator device on the wearer""s head, the coupling further including at least a first member, the actuator being operatively yet releasably connected with the first member of the coupling; and the actuator releasing the first member of the coupling to break the coupling and release the respirator device when the pressure of the breathable gas being simultaneously supplied to the respirator device and to the actuator drops below a minimum maintenance pressure above the ambient atmospheric pressure around the respirator device to operate the respirator device.
In yet another aspect, the invention is a method of automatically releasing a respirator device at least from a wearer""s face, the method comprising the steps of: supplying pressurized breathable gas at least at a predetermined initial minimum pressure simultaneously to the respirator device and to an actuator of a coupling releasably securing the respirator device on the wearer""s head, the coupling further including at least a first member, the actuator being operatively yet releasably connected with the first member of the coupling; and pressurizing the wearer together with the respirator device and coupling in a hyperbaric chamber with a breathable gas while simultaneously supplying to each of the actuator and the respirator device inner side, a breathable gas different in oxygen content from the breathable gas pressurizing the hyperbaric chamber.